The amoeba thrives in warm, fresh water and can grow in bore water if it's pumped to the surface and left untreated.

Associate professor Stuart Khan from the University of New South Wales said there's no chance the parasite could live in water treated for drinking in the way Broken Hill's supply is, whether it's drawn from surface or bore water.

"Naegleria Fowleri will not pass through a reverse osmosis membrane," Dr Khan said, referring to the city's desalination plant which will be switched on next month.

"And you also have chlorine, so that water that's delivered from the water treatment plant through to customers will be chlorinated.

"And fortunately Naegleria Fowleri, unlike some other similar organisms, is actually quite susceptible to chlorination, it's easy to kill by chlorine disinfection."

Dr Khan said there shouldn't be concern about the safety of bores as a source of drinking water.

"You wouldn't select water from a bore for a drinking water supply if you knew that [contaminants] were a significant problem, and if you did, you would apply the appropriate treatment processes in order to control them," he said.

Authorities expect to begin drawing the city's water supply from bores towards the end of next year if there are no major inflows into the Menindee Lakes before then.

Meanwhile, a desalination plant is due to be switched on next month as the dwindling surface water supply becomes saltier.

"I wouldn't imagine that this is going to lead to people being exposed to unsafe concentrations of trace chemicals," Dr Khan said.